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1.
Proc Natl Acad Sci U S A ; 121(20): e2320674121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38684007

RESUMO

Identifying and protecting hotspots of endemism and species richness is crucial for mitigating the global biodiversity crisis. However, our understanding of spatial diversity patterns is far from complete, which severely limits our ability to conserve biodiversity hotspots. Here, we report a comprehensive analysis of amphibian species diversity in China, one of the most species-rich countries on Earth. Our study combines 20 y of field surveys with new molecular analyses of 521 described species and also identifies 100 potential cryptic species. We identify 10 hotspots of amphibian diversity in China, each with exceptional species richness and endemism and with exceptional phylogenetic diversity and phylogenetic endemism (based on a new time-calibrated, species-level phylogeny for Chinese amphibians). These 10 hotspots encompass 59.6% of China's described amphibian species, 49.0% of cryptic species, and 55.6% of species endemic to China. Only four of these 10 hotspots correspond to previously recognized biodiversity hotspots. The six new hotspots include the Nanling Mountains and other mountain ranges in South China. Among the 186 species in the six new hotspots, only 9.7% are well covered by protected areas and most (88.2%) are exposed to high human impacts. Five of the six new hotspots are under very high human pressure and are in urgent need of protection. We also find that patterns of richness in cryptic species are significantly related to those in described species but are not identical.


Assuntos
Anfíbios , Biodiversidade , Filogenia , Animais , Anfíbios/classificação , China , Conservação dos Recursos Naturais
2.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(5): 859-862, 2023 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-37927029

RESUMO

Sporadic Creutzfeldt-Jakob disease(sCJD)is a prion-caused degenerative disease of the central nervous system,with the typical clinical manifestation of rapidly progressive dementia.The course of disease is less than 1 year in most patients and more than 2 years in only 2% to 3% patients.We reported a case of sCJD with expressive language disorder and slow progression in this paper.By summarizing the clinical manifestations and the electroencephalograhpy,MRI,and pathological features,we aimed to enrich the knowledge about the sCJD with slow progression.


Assuntos
Síndrome de Creutzfeldt-Jakob , Humanos , Síndrome de Creutzfeldt-Jakob/diagnóstico por imagem , Síndrome de Creutzfeldt-Jakob/patologia , Encéfalo/patologia , Imageamento por Ressonância Magnética , Sistema Nervoso Central/patologia
5.
Cell ; 186(14): 2959-2976.e22, 2023 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-37339633

RESUMO

Snakes are a remarkable squamate lineage with unique morphological adaptations, especially those related to the evolution of vertebrate skeletons, organs, and sensory systems. To clarify the genetic underpinnings of snake phenotypes, we assembled and analyzed 14 de novo genomes from 12 snake families. We also investigated the genetic basis of the morphological characteristics of snakes using functional experiments. We identified genes, regulatory elements, and structural variations that have potentially contributed to the evolution of limb loss, an elongated body plan, asymmetrical lungs, sensory systems, and digestive adaptations in snakes. We identified some of the genes and regulatory elements that might have shaped the evolution of vision, the skeletal system and diet in blind snakes, and thermoreception in infrared-sensitive snakes. Our study provides insights into the evolution and development of snakes and vertebrates.


Assuntos
Genoma , Serpentes , Animais , Serpentes/genética , Adaptação Fisiológica , Aclimatação , Evolução Molecular , Filogenia , Evolução Biológica
6.
Front Neurol ; 14: 1103026, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37181574

RESUMO

Objectives: We aimed to determine a method to identify normal cerebrospinal fluid (CSF) glucose levels by examining the correlation between blood and CSF glucose levels in patients with normal and abnormal glucose metabolism. Methods: One hundred ninety-five patients were divided into two groups according to their glucose metabolism. The glucose levels were obtained from CSF and fingertip blood at 6, 5, 4, 3, 2, 1, and 0 h before lumbar puncture. SPSS 22.0 software was used for the statistical analysis. Results: In both the normal and abnormal glucose metabolism groups, CSF glucose levels increased with blood glucose levels at 6, 5, 4, 3, 2, 1, and 0 h before lumbar puncture. In the normal glucose metabolism group, the CSF/blood glucose ratio range was 0.35-0.95 at 0-6 h before lumbar puncture, and the CSF/average blood glucose ratio range was 0.43-0.74. In the abnormal glucose metabolism group, the CSF/blood glucose ratio range was 0.25-1.2 at 0-6 h before lumbar puncture, and the CSF/average blood glucose ratio range was 0.33-0.78. Conclusion: The CSF glucose level is influenced by the blood glucose level 6 h before lumbar puncture. In patients with normal glucose metabolism, direct measurement of the CSF glucose level can be used to determine whether the CSF level is normal. However, in patients with abnormal or unclear glucose metabolism, the CSF/average blood glucose ratio should be used to determine whether the CSF glucose level is normal.

7.
Sci China Life Sci ; 66(10): 2399-2414, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37256419

RESUMO

Limb loss shows recurrent phenotypic evolution across squamate lineages. Here, based on three de novo-assembled genomes of limbless lizards from different lineages, we showed that divergence of conserved non-coding elements (CNEs) played an important role in limb development. These CNEs were associated with genes required for limb initiation and outgrowth, and with regulatory signals in the early stage of limb development. Importantly, we identified the extensive existence of insertions and deletions (InDels) in the CNEs, with the numbers ranging from 111 to 756. Most of these CNEs with InDels were lineage-specific in the limbless squamates. Nearby genes of these InDel CNEs were important to early limb formation, such as Tbx4, Fgf10, and Gli3. Based on functional experiments, we found that nucleotide mutations and InDels both affected the regulatory function of the CNEs. Our study provides molecular evidence underlying limb loss in squamate reptiles from a developmental perspective and sheds light on the importance of regulatory element InDels in phenotypic evolution.


Assuntos
Genoma , Répteis , Animais , Répteis/genética , Fatores de Transcrição/genética , Evolução Molecular , Sequência Conservada/genética , Evolução Biológica
8.
Genome Biol ; 24(1): 46, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36895044

RESUMO

BACKGROUND: Reptiles exhibit a wide variety of skin colors, which serve essential roles in survival and reproduction. However, the molecular basis of these conspicuous colors remains unresolved. RESULTS: We investigate color morph-enriched Asian vine snakes (Ahaetulla prasina), to explore the mechanism underpinning color variations. Transmission electron microscopy imaging and metabolomics analysis indicates that chromatophore morphology (mainly iridophores) is the main basis for differences in skin color. Additionally, we assemble a 1.77-Gb high-quality chromosome-anchored genome of the snake. Genome-wide association study and RNA sequencing reveal a conservative amino acid substitution (p.P20S) in SMARCE1, which may be involved in the regulation of chromatophore development initiated from neural crest cells. SMARCE1 knockdown in zebrafish and immunofluorescence verify the interactions among SMARCE1, iridophores, and tfec, which may determine color variations in the Asian vine snake. CONCLUSIONS: This study reveals the genetic associations of color variation in Asian vine snakes, providing insights and important resources for a deeper understanding of the molecular and genetic mechanisms related to reptilian coloration.


Assuntos
Cromatóforos , Estudo de Associação Genômica Ampla , Animais , Peixe-Zebra/genética , Pigmentação da Pele , Serpentes/genética , Cor , Proteínas de Peixe-Zebra , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética
9.
Mol Ecol Resour ; 23(5): 1124-1141, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36924341

RESUMO

DNA barcoding has greatly facilitated studies of taxonomy, biodiversity, biological conservation, and ecology. Here, we establish a reliable DNA barcoding library for Chinese snakes, unveiling hidden diversity with implications for taxonomy, and provide a standardized tool for conservation management. Our comprehensive study includes 1638 cytochrome c oxidase subunit I (COI) sequences from Chinese snakes that correspond to 17 families, 65 genera, 228 named species (80.6% of named species) and 36 candidate species. A barcode gap analysis reveals gaps, where all nearest neighbour distances exceed maximum intraspecific distances, in 217 named species and all candidate species. Three species-delimitation methods (ABGD, sGMYC, and sPTP) recover 320 operational taxonomic units (OTUs), of which 192 OTUs correspond to named and candidate species. Twenty-eight other named species share OTUs, such as Azemiops feae and A. kharini, Gloydius halys, G. shedaoensis, and G. intermedius, and Bungarus multicinctus and B. candidus, representing inconsistencies most probably caused by imperfect taxonomy, recent and rapid speciation, weak taxonomic signal, introgressive hybridization, and/or inadequate phylogenetic signal. In contrast, 43 species and candidate species assign to two or more OTUs due to having large intraspecific distances. If most OTUs detected in this study reflect valid species, including the 36 candidate species, then 30% more species would exist than are currently recognized. Several OTU divergences associate with known biogeographic barriers, such as the Taiwan Strait. In addition to facilitating future studies, this reliable and relatively comprehensive reference database will play an important role in the future monitoring, conservation, and management of Chinese snakes.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico , Humanos , Animais , Filogenia , Código de Barras de DNA Taxonômico/métodos , Serpentes/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética
10.
Conserv Biol ; 37(4): e14069, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36751969

RESUMO

Over the past 40 years, the climate has been changing and human disturbance has increased in the vast Qinghai-Tibet Plateau (QTP). These 2 factors are expected to affect the distribution of a large number of endemic vertebrate species. However, quantitative relationships between range shifts and climate change and human disturbance of these species in the QTP have rarely been evaluated. We used occurrence records of 19 terrestrial vertebrate species (birds, mammals, amphibians, and reptiles) occurring in the QTP from 1980 to 2020 to quantify the effects of climate change and anthropogenic impacts on the distribution of these 4 taxonomic groups and estimated species range changes in each species. The trend in distribution changes differed among the taxonomic groups, although, generally, ranges shifted to central QTP. Climate change contributed more to range variation than human disturbance (the sum of the 4 climatic variables contributed more than the sum of the 4 human disturbance variables for all 4 taxonomic groups). Suitable geographic range increased for most mammals, amphibians, and reptiles (+27.6%, +18.4%, and +27.8% on average, respectively), whereas for birds range decreased on average by 0.9%. Quantitative evidence for climate change and human disturbance associations with range changes for endemic vertebrate species in the QTP can provide useful insights into biodiversity conservation under changing environments.


En los últimos 40 años, el clima ha cambiado y las perturbaciones humanas han aumentado en la vasta meseta Qinghai-Tíbet (MQT). Se espera que estos dos factores afecten la distribución de un gran número de especies de vertebrados endémicos. Sin embargo, las relaciones cuantitativas entre los cambios del área de distribución y el cambio climático y las perturbaciones humanas en estas especies de la MQT han sido poco evaluadas. Utilizamos los registros de presencia de 19 especies de vertebrados terrestres (aves, mamíferos, anfibios y reptiles) de la MQT tomados entre 1980 y 2020 para cuantificar los efectos del cambio climático y los impactos antropogénicos sobre la distribución de estos cuatro grupos taxonómicos y estimar los cambios en el área de distribución de cada especie. La tendencia en los cambios de distribución difirió entre los grupos taxonómicos, aunque, en general, las áreas de distribución se desplazaron hacia el centro de la MQT. El cambio climático contribuyó más a la variación del área de distribución que las perturbaciones humanas (la suma de las cuatro variables climáticas contribuyó más que la suma de las cuatro variables de perturbaciones humanas para los cuatro grupos taxonómicos). El área de distribución geográfica adecuada aumentó para la mayoría de los mamíferos, anfibios y reptiles (+27.6%, +18.4% y +27.8% en promedio, respectivamente), mientras que para las aves disminuyó en promedio un 0.9%. Las pruebas cuantitativas de la asociación del cambio climático y las perturbaciones humanas con los cambios en el área de distribución de las especies vertebradas endémicas de la MQT pueden aportar información útil para la conservación de la biodiversidad en entornos cambiantes.


Assuntos
Efeitos Antropogênicos , Mudança Climática , Animais , Humanos , Tibet , Conservação dos Recursos Naturais , Vertebrados , Mamíferos
11.
Mol Ecol ; 32(6): 1335-1350, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36073004

RESUMO

Understanding how and why species evolve requires knowledge on intraspecific divergence. In this study, we examined intraspecific divergence in the endangered hot-spring snake (Thermophis baileyi), an endemic species on the Qinghai-Tibet Plateau (QTP). Whole-genome resequencing of 58 sampled individuals from 15 populations was performed to identify the drivers of intraspecific divergence and explore the potential roles of genes under selection. Our analyses resolved three groups, with major intergroup admixture occurring in regions of group contact. Divergence probably occurred during the Pleistocene as a result of glacial climatic oscillations, Yadong-Gulu rift, and geothermal fields differentiation, while complex gene flow between group pairs reflected a unique intraspecific divergence pattern on the QTP. Intergroup fixed loci involved selected genes functionally related to divergence and local adaptation, especially adaptation to hot spring microenvironments in different geothermal fields. Analysis of structural variants, genetic diversity, inbreeding, and genetic load indicated that the hot-spring snake population has declined to a low level with decreased diversity, which is important for the conservation management of this endangered species. Our study demonstrated that the integration of demographic history, gene flow, genomic divergence genes, and other information is necessary to distinguish the evolutionary processes involved in speciation.


Assuntos
Variação Genética , Fontes Termais , Humanos , Animais , Tibet , Variação Genética/genética , Filogenia , Uganda , Serpentes/genética , Genômica
12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-981280

RESUMO

Objective To investigate the influencing factors and establish a model predicting the performance of needle visualization in fine-needle aspiration (FNA) of thyroid nodules. Methods This study prospectively included 175 patients who underwent FNA of thyroid nodules in the Department of Ultrasound in China-Japan Friendship Hospital and compared the display of the needle tips in the examination of 199 thyroid nodules before and after the application of needle visualization.We recorded the location,the positional relationship with thyroid capsule,ultrasonic characteristics,and the distribution of the soft tissue strip structure at the puncture site of the nodules with unclear needle tips display before using needle visualization.Furthermore,according to the thyroid imaging reporting and data system proposed by the American College of Radiology,we graded the risk of the nodules.Lasso-Logistic regression was employed to screen out the factors influencing the performance of needle visualization and establish a nomogram for prediction. Results The needle tips were not clearly displayed in the examination of 135 (67.8%) and 53 (26.6%) nodules before and after the application of needle visualization,respectively,which showed a significant difference (P<0.001).Based on the positional relationship between the nodule and capsule,anteroposterior/transverse diameter (A/T) ratio,blood supply,and the distribution of subcutaneous strip structure at the puncture site,a nomogram was established to predict the probability of unclear display of the needle tips after application of needle visualization.The C-index of the prediction model was 0.75 (95%CI=0.67-0.84) and the area under the receiver operating characteristic curve was 0.72.The calibration curve confirmed the appreciable reliability of the prediction model,with the C-index of 0.70 in internal validation. Conclusions Needle visualization can improve the display of the needle tip in ultrasound-guided FNA of thyroid nodules.The nomogram established based on ultrasound features such as the positional relationship between the nodule and capsule,A/T ratio,blood supply,and the distribution of subcutaneous strip structure at the puncture site can predict whether needle visualization is suitable for the examination of nodules.


Assuntos
Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Biópsia por Agulha Fina/métodos , Reprodutibilidade dos Testes , Ultrassonografia , Estudos Retrospectivos , Neoplasias da Glândula Tireoide
13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-981278

RESUMO

Objective To establish a nomogram for predicting the risk of cervical lymph node metastasis in differentiated thyroid carcinoma (DTC). Methods The patients with complete clinical data of DTC and cervical lymph node ultrasound and diagnosed based on pathological evidence from January 2019 to December 2021 were assigned into a training group (n=444) and a validation group (n=125).Lasso regression was performed to screen the data with differences between groups,and multivariate Logistic regression to establish a prediction model with the factors screened out by Lasso regression.C-index and calibration chart were employed to evaluate the prediction performance of the established model. Results The predictive factors for establishing the model were lymph node short diameter≥0.5 cm,long-to-short-axis ratio<2,disappearance of lymph node hilum,cystic transformation,hyperechogenicity,calcification,and abnormal blood flow (all P<0.001).The established model demonstrated a good discriminative ability,with the C index of 0.938 (95%CI=0.926-0.961) in the training group. Conclusion The nomogram established based on the ultrasound image features of cervical lymph nodes in DTC can accurately predict the risk of cervical lymph node metastasis in DTC.


Assuntos
Humanos , Nomogramas , Metástase Linfática , Linfonodos/patologia , Pescoço/patologia , Neoplasias da Glândula Tireoide/patologia , Adenocarcinoma/patologia , Estudos Retrospectivos
14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-996082

RESUMO

As an important measure starting for hospital management, hospital accreditation can effectively guide hospitals to improve their comprehensive service capabilities and management level. The accreditation results of 38 tertiary general hospitals in Jiangsu province from 2018 to 2020 showed that there were weaknesses existing in the development of hospitals, including the radiosity and influence of tertiary hospitals, patient service mode, construction of medical technology capabilities and disciplines, medical quality and safety, nursing quality management and specialized nursing, and information construction. The author suggested that hospitals should return to functional positioning, improve the service quality, strengthen construction of hospital disciplines and technical projects, consolidate the foundation of quality and safety management, improve the level of information technology construction, for references for promoting the high-quality sustainable development of tertiary general hospitals.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1008141

RESUMO

Sporadic Creutzfeldt-Jakob disease(sCJD)is a prion-caused degenerative disease of the central nervous system,with the typical clinical manifestation of rapidly progressive dementia.The course of disease is less than 1 year in most patients and more than 2 years in only 2% to 3% patients.We reported a case of sCJD with expressive language disorder and slow progression in this paper.By summarizing the clinical manifestations and the electroencephalograhpy,MRI,and pathological features,we aimed to enrich the knowledge about the sCJD with slow progression.


Assuntos
Humanos , Síndrome de Creutzfeldt-Jakob/patologia , Encéfalo/patologia , Imageamento por Ressonância Magnética , Sistema Nervoso Central/patologia
16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-973247

RESUMO

ObjectiveTo reveal the molecular pathogenesis of Hunter syndrome in three families in southern China and to clarify the correlation between phenotype and genotype, so as to lay a foundation for future prenatal or preimplantation genetic diagnosis. MethodsOn the basis of initial clinical diagnosis and pedigree analysis, qualitative detection of glycosaminoglycans in urine was performed first, and then anticoagulant blood samples were collected from the children and their relatives. DNA was extracted and the IDS gene sequence was analyzed by PCR and Sanger sequencing. Various methods such as RT-PCR and bioinformatics analysis were used to identify the pathogenicity of the new variants. ResultsThe urine test results of the patients in the three families were all strongly positive(++). Probands were all male, with hemizygous mutations in IDS gene from their mothers, and the mutation sites were c.615_622delCATACAGT, c.847_848delGT and IVS7 ds+1 G>A, respectively. The cross-species conservation analysis showed that the amino acid of IDS gene mutation site was highly conserved during species evolution. Compared with the normal protein, mutant proteins exhibited significant differences in the predicted results of advanced structure. The variants identified in the three families were classified as pathogenic by ACMG criteria. ConclusionsThe three probands were diagnosed with Hunter syndrome. The c.615_622del(p.Il206Valfs*18), c.847_848del(p.Val283Alafs*57) and IVS7 ds+1 G>A (p.G336Dfs*12) of IDS gene are all novel pathogenic mutations, which are the underlying causes of morbidity in children. This study has further enriched the mutation spectrum of IDS gene.

17.
Int J Mol Sci ; 23(17)2022 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-36077479

RESUMO

Anan's rock agama (Laudakia sacra) is a lizard species endemic to the harsh high-altitude environment of the Qinghai-Tibet Plateau, a region characterized by low oxygen tension and high ultraviolet (UV) radiation. To better understand the genetic mechanisms underlying highland adaptation of ectotherms, we assembled a 1.80-Gb L. sacra genome, which contained 284 contigs with an N50 of 20.19 Mb and a BUSCO score of 93.54%. Comparative genomic analysis indicated that mutations in certain genes, including HIF1A, TIE2, and NFAT family members and genes in the respiratory chain, may be common adaptations to hypoxia among high-altitude animals. Compared with lowland reptiles, MLIP showed a convergent mutation in L. sacra and the Tibetan hot-spring snake (Thermophis baileyi), which may affect their hypoxia adaptation. In L. sacra, several genes related to cardiovascular remodeling, erythropoiesis, oxidative phosphorylation, and DNA repair may also be tailored for adaptation to UV radiation and hypoxia. Of note, ERCC6 and MSH2, two genes associated with adaptation to UV radiation in T. baileyi, exhibited L. sacra-specific mutations that may affect peptide function. Thus, this study provides new insights into the potential mechanisms underpinning high-altitude adaptation in ectotherms and reveals certain genetic generalities for animals' survival on the plateau.


Assuntos
Altitude , Lagartos , Adaptação Fisiológica/genética , Animais , Hipóxia/genética , Sacro , Seleção Genética , Serpentes , Tibet
18.
Innovation (Camb) ; 3(5): 100295, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36032194

RESUMO

Animals have evolved sophisticated temperature-sensing systems and mechanisms to detect and respond to ambient temperature changes. As a relict species endemic to the Qinghai-Tibet Plateau, hot-spring snake (Thermophis baileyi) survived the dramatic changes in climate that occurred during plateau uplift and ice ages, providing an excellent opportunity to explore the evolution of temperature sensation in ectotherms. Based on distributional information and behavioral experiments, we found that T. baileyi prefer hot-spring habitats and respond more quickly to warmth than other two snakes, suggesting that T. baileyi may evolve an efficient thermal-sensing system. Using high-quality chromosome-level assembly and comparative genomic analysis, we identified cold acclimation genes experiencing convergent acceleration in high-altitude lineages. We also discovered significant evolutionary changes in thermosensation- and thermoregulation-related genes, including the transient receptor potential (TRP) channels. Among these genes, TRPA1 exhibited three species-specific amino acid replacements, which differed from those found in infrared imaging snakes, implying different temperature-sensing molecular strategies. Based on laser-heating experiments, the T. baileyi-specific mutations in TRPA1 resulted in an increase in heat-induced opening probability and thermal sensitivity of the ion channels under the same degree of temperature stimulation, which may help the organism respond to temperature changes more quickly. These results provide insight into the genetic mechanisms underpinning the evolution of temperature-sensing strategies in ectotherms as well as genetic evidence of temperature acclimation in this group.

19.
Cell Rep ; 40(2): 111079, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35830808

RESUMO

Bungarus multicinctus is a widely distributed and medically important elapid snake that produces lethal neurotoxic venom. To study and enhance existing antivenom, we explore the complete repertoire of its toxin genes based on de novo chromosome-level assembly and multi-tissue transcriptome data. Comparative genomic analyses suggest that the three-finger toxin family (3FTX) may evolve through the neofunctionalization of flanking LY6E. A long-neglected 3FTX subfamily (i.e., MKA-3FTX) is also investigated. Only one MKA-3FTX gene, which evolves a different protein conformation, is under positive selection and actively transcribed in the venom gland, functioning as a major toxin effector together with MKT-3FTX subfamily homologs. Furthermore, this lethal snake may acquire self-resistance to its ß-bungarotoxin via amino acid replacements on fast-evolving KCNA2. This study provides valuable resources for further evolutionary and structure-function studies of snake toxins, which are fundamental for the development of effective antivenoms and drug candidates.


Assuntos
Venenos Elapídicos , Elapidae , Animais , Antivenenos/química , Antivenenos/metabolismo , Bungarus/metabolismo , Venenos Elapídicos/química , Venenos Elapídicos/metabolismo , Venenos Elapídicos/toxicidade , Elapidae/genética , Elapidae/metabolismo , Toxinas Três Dedos
20.
PeerJ ; 10: e12999, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35261821

RESUMO

Ecological niche modeling is a tool used to determine current potential species' distribution or habitat suitability models which can then be used to project suitable areas in time. Projections of suitability into past climates can identify locations of climate refugia, or areas with high climatic stability likely to contain the highest levels of genetic diversity and stable populations when climatic conditions are less suitable in other parts of the range. Modeling habitat suitability for closely related species in recent past can also reveal potential periods and regions of contact and possible admixture. In the east palearctic, there are five Dryophytes (Hylid treefrog) clades belonging to two groups: Dryophytes japonicus group: Clades A and B; and Dryophytes immaculatus group: Dryophytes immaculatus, Dryophytes flaviventris, and Dryophytes suweonensis. We used maximum entropy modeling to determine the suitable ranges of these five clades during the present and projected to the Last Glacial Maximum (LGM) and Last Interglacial (LIG) periods. We also calculated climatic stability for each clade to identify possible areas of climate refugia. Our models indicated suitable range expansion during the LGM for four clades with the exclusion of D. immaculatus. High climatic stability in our models corresponded to areas with the highest numbers of recorded occurrences in the present. The models produced here can additionally serve as baselines for models of suitability under climate change scenarios and indicate species ecological requirements.


Assuntos
Ecossistema , Modelos Teóricos , Animais , Filogeografia , Dinâmica Populacional , Anuros
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